The generic name of Betalucel is Metoprolol. Metoprolol does not cause excessive occurrence of premature beats and can effectively treat premature beats. Metoprolol is a β-blocker, which can block the β-receptors of cardiomyocytes, inhibit the increase of pacing current, sodium current and L-type calcium current caused by sympathetic nerve activity and reduce the autoregulation, so it will not cause excessive premature beats, and it can be used to treat premature beats effectively. Metoprolol is used in the treatment of hypertension, angina pectoris, myocardial infarction, hypertrophic cardiomyopathy, aortic coarctation, arrhythmia, hyperthyroidism, cardiac neurosis. Cardiogenic shock, sick sinus node syndrome, atrioventricular block of the II and III degrees, patients with unstable, decompensated heart failure, bradycardia or hypotension, hypersensitivity to the components of the preparation of metoprolol is contraindicated. It is contraindicated in pregnant and lactating women, and should be used with caution in severe hepatic impairment, severe renal impairment, severe emergencies accompanied by metabolic acidosis and when combined with digitalis, dizziness and fatigue may occur during administration. Patients with premature beats should go to the hospital in time when obvious symptoms occur, please use the drug under the guidance of the doctor.